CEL is on, and DTC is "Idle Air Control Valve (failsafe)"
The IAC is fine. I replaced, thinking it was the problem. No luck. I am told that the IAC Failsafe DTC indicates that some other problem is causing the IAC to go into its failsafe mode.
The car will start and idle fine. Then, occasionally it will stall when pushing the clutch in (coming to a stop, etc.), or simply idle at very low RPMs (200-350), and run very rough. All it takes to correct the problem is to shut down the car, allow the computer to reset, and then start it again. It runs fine.
It seemed completely random at first, but I have noticed on common factor. Nearly every time this has occurred, it occurred in conjunction with another problem: the speedometer malfunctioning. Often, the speedometer will not work, and will come on and off at random. The stalls/rough running seem to occur after an episode with the speedometer.
Are these actually related, or is this simply a coincidence? What is the cause of these issues, and how can it be repaired? Other attempts to repair the issue have included replacing the speed sensor, and an engine knock sensor.
The IAC is fine. I replaced, thinking it was the problem. No luck. I am told that the IAC Failsafe DTC indicates that some other problem is causing the IAC to go into its failsafe mode.
The car will start and idle fine. Then, occasionally it will stall when pushing the clutch in (coming to a stop, etc.), or simply idle at very low RPMs (200-350), and run very rough. All it takes to correct the problem is to shut down the car, allow the computer to reset, and then start it again. It runs fine.
It seemed completely random at first, but I have noticed on common factor. Nearly every time this has occurred, it occurred in conjunction with another problem: the speedometer malfunctioning. Often, the speedometer will not work, and will come on and off at random. The stalls/rough running seem to occur after an episode with the speedometer.
Are these actually related, or is this simply a coincidence? What is the cause of these issues, and how can it be repaired? Other attempts to repair the issue have included replacing the speed sensor, and an engine knock sensor.
Mar 23, 2009 at 11:24 AM